During 1948, 803 tests were drilled in the South Louisiana district. Of these, 129 or 16.1 per cent were rank wildcat exploratory tests and 674 or 83.9 per cent were field development tests. The 129 rank wildcat tests resulted in the discovery of 28 new fields. All successful field exploratory wells are classified as follows: new-pool wells, 29; shallower-pool wells, 3; deeper-pool wells, 8; and outpost wells, 38.

Of the 674 field development tests, 463 or 68.9 per cent were successful and 211 were failures. There was an increase of 24.3 per cent in the number drilled in 1948 over 1947.

The 28 new field discoveries include 13 oil fields, 11 condensate fields, and 4 gas fields. Of great significance is the fact that 7 of the new fields were discovered in the open waters of the Gulf of Mexico, 3 of which are oil fields, 2 condensate fields, and 2 gas fields.

Seismograph operations are credited with having led to 22 of the new-field discoveries, subsurface led to 2, and a combination of seismograph and subsurface was responsible for the remaining 4.

The small decrease in the number of seismograph crews operating in offshore waters was equalized by an increase in the number of inshore crews. The number of gravity-meter crews operating in the offshore areas decreased almost to zero during the year. This appears to indicate a general decline in offshore geophysical exploratory and reconnaissance activities. The number of land gravity meter crews increased to a maximum in the summer months and then decreased during the remainder of the year.

The most significant exploratory activity in 1948 was made in the offshore Miocene trend. There has been a noticeable increase in geophysical and leasing activities in the area northeast of the Mississippi River.